This was announced on the News
English Heritage have set up a site "Britain from above" http://www.britainfromabove.org.uk/
with aerial photos from as early as 1919. A few on Wirral. Site is very slow, probably because it's new but I eventually managed to download some. I hope that when it gets less busy, it'll speed up.
Church Rd. 1920. Mersey Park school bottom right
Mersey Park 1920
King's Lane estate 1926. King's Rd. at bottom, King's Lane at right, Princes Boulevard at left.